Enzymatic changes and cytotoxic effects of Metarhizium anisopliae fungal extracts on the Egyptian cotton leaf worm Spodoptera littoralis (SL 96) cell line.

The extra-and intra-cellular extracts of two Metarhizium anisopliae isolates: Ma23 and MR3, were introduced to a cell line of Spodoptera littoralis. The cell line (Sl96) was established in the Entomovirology centre from S. littoralis ovaries. MR3 extracellular fluid-treated culture had an increase in the Acid phosphatase (AcP) level as compared either to the untreated cell line or to the fungal extract alone. Moreover, the enzymatic tests showed that alpha and beta-glucosidases have been detected only after the treatment with extracellular fluid of MR3. The elevation of AcP level that appeared after the treatment of MR3 coincided with a conspicuous decrease of about one third of the initial number (96 x 10(3)) of the Sl96 cell. vacuolization and lysis of some cells. Deformation of the cells and shrinkage of cell membrane have been observed in the case of Ma23 treatments. Crystal formation was restricted to the treatment of MR3 extracellular extract. The results are discussed in the light of the possibility that the cytotoxic effects and enzymatic changes are attributed to the virulence of the fungal isolates.